Valmiki Ramayana Ayodhya Kanda Sarga 91 Shloka 82
Original Shlokaइत्येवं रममाणानां देवानामिव नन्दने। भरद्वाजाश्रमे रम्ये सा रात्रिर्व्यत्यवर्तत।।2.91.82।।
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इत्येवम् like this, नन्दने in the garden of Indra, देवानामिव as for gods, रम्ये in the lovely, भरद्वाजाश्रमे in Bharadwaja's hermitage, रममाणानाम् enjoying so, सा रात्रिः that night, व्यत्यवर्तत passed off.
As they were enjoying themselves in Bharadwaja's hermitage like the gods in the garden of Indra the night wore off.